small refugium inside the display tank: Is it possible?

[reef4life!!!]

Hi everyone,as my phosphates don't come down i thought of an (stupid probably) idea about setting a small refugium.The idea was to place these things shown in the pictures below and inside of those to put a cheato inside, close it and put it inside a corner in my tank and just put some rocks maybe in front so it's not visible. Could this possibly work or I just make the worst ever post

 

[reef4life!!!]

Any chance you can handle a HOB refugium? Fijicube makes a nice one.
I added one to a 90-gal DT setup peninsula style. Hung it off the end and added an inexpensive cannabis LED grow light to the outside of the fuge. Works great, grows chaeto and sea lettuce like crazy!

Also i forgot to ask,which is the best macroalgae for reducing phosphates?I don't really have to reduce nitrates as are stable at very low ranges 2-5ppm so my main issue is my phosphates but if i put a macroalgae that consumes much more nitrates then i would have to dose nitrates to keep them up haha...(i know the general rule is that macroalgae consumes more nitrates than phosphates)